Update readme with multichain stuff (#32)

Author: krzkaczor

README.md

@@ -24,7 +24,7 @@ While browsing smart contract code on [Etherscan](https://etherscan.io/) just ch
 
 - frictionless - just tweak URL while browsing etherscan `.io` -> `deth.net`
 - proxy support - automatically follows proxies and displays implementation source code
-- multichain - supports many etherscan instances (testnets, L2s, L1s) (COMING SOON)
+- multichain - supports different etherscan instances: testnets, L2s, L1s ([all supported chains](https://github.com/dethcrypto/ethereum-code-viewer/blob/main/packages/ethereum-viewer/src/explorer/networks.ts))
 
 ## Motivation
 
@@ -34,9 +34,10 @@ Ethereum Code Viewer was born out of frustration, and it's here to fix all of th
 
 ## Examples
 
-- Arbitrum ERC20 Gateway: [Ethereum Code Viewer](https://etherscan.deth.net/address/0xa3a7b6f88361f48403514059f1f16c8e78d60eec#code) | [etherscan](https://etherscan.io/address/0xa3a7b6f88361f48403514059f1f16c8e78d60eec#code)
-- Optimism L1CrossDomainMessenger: [Ethereum Code Viewer](https://etherscan.deth.net/address/0x25ace71c97b33cc4729cf772ae268934f7ab5fa1#code) | [etherscan](https://etherscan.io/address/0x25ace71c97b33cc4729cf772ae268934f7ab5fa1#code)
-- Dai Stablecoin: [Ethereum Code Viewer](https://etherscan.deth.net/address/0x6b175474e89094c44da98b954eedeac495271d0f#code) | [etherscan](https://etherscan.io/address/0x6b175474e89094c44da98b954eedeac495271d0f#code)
+- Arbitrum ERC20 Gateway on mainnet: [Ethereum Code Viewer](https://etherscan.deth.net/address/0xa3a7b6f88361f48403514059f1f16c8e78d60eec) | [etherscan](https://etherscan.io/address/0xa3a7b6f88361f48403514059f1f16c8e78d60eec#code)
+- Arbitrum ERC20 Gateway on arbitrum: [Ethereum Code Viewer](https://arbiscan.deth.net/address/0x09e9222e96e7b4ae2a407b98d48e330053351eee) | [arbiscan](https://arbiscan.io/address/0x09e9222e96e7b4ae2a407b98d48e330053351eee#code)
+- Optimism L1CrossDomainMessenger: [Ethereum Code Viewer](https://etherscan.deth.net/address/0x25ace71c97b33cc4729cf772ae268934f7ab5fa1) | [etherscan](https://etherscan.io/address/0x25ace71c97b33cc4729cf772ae268934f7ab5fa1#code)
+- Dai Stablecoin: [Ethereum Code Viewer](https://etherscan.deth.net/address/0x6b175474e89094c44da98b954eedeac495271d0f) | [etherscan](https://etherscan.io/address/0x6b175474e89094c44da98b954eedeac495271d0f#code)
 
 ## Contributing